Broadband data communications links today are commonly shared by hundreds or thousands, if not millions, of independent users or user groups. Each of these users or user groups has their own specific bandwidth and usage requirements of a communications system. Unfortunately, in both wireline packet-based communications systems and wireless broadband communications systems, a majority of system bandwidth is often consumed by a small proportion of a system's total users. This can be due to the fact that heavy-users may continually be downloading large media data files (e.g., movies, music, eBooks, etc.) over a shared communications link with a larger number of light to moderate users who may only intermittently require access to much smaller media data files (e.g., websites, email, private service accounts, etc.). In this scenario, it would not be uncommon for up to 90% of a communication system's bandwidth to be consumed by as little as 10% of the system's users.
This disproportionate usage of bandwidth can cause a communications system's average per-user throughput to be significantly reduced. System average throughput may be defined as the sum of the data rates that are delivered to all users in a networked data communications system divided by the number of users. Decreased per-user throughput is most often affiliated with a state of network congestion, which can negatively impact several important quality of service (QOS) metrics, including delayed queuing, data loss, dropping existing connections, blocking new connections, etc.
QOS relates to a data communications system's ability to provide users or data flows on a shared data communications link a guarantee of a certain level of performance associated with the various QOS metrics. For example, a predetermined data transfer rate, queuing delay, or connection stability may be identified as specific QOS guarantees. These guarantees are very important for many modern data communications media, such as for real-time streaming audiovisual data, voice-over IP data, cellular communication data, etc., since this sensitive media content may require certain QOS guarantees to function properly.
In many data communication systems today users acquire service by paying flat rate fees. In these systems bandwidth allocation for a specific user is typically based on that user's bandwidth consumption profile, which is evaluated independently from any other user on the same data communications link. In these systems, a network operator may limit the amount of bandwidth consumed by the system's heaviest users, simply by reducing those user's data transfer rates for a set period of time. This bandwidth allocation scheme is typically implemented when an individual user's allowed bandwidth consumption has been exceeded. Although this solution may allow for more users to transfer data using the same data communication link, it does not ensure full usage of the communications system's bandwidth at all times. Further, this allocation scheme does not give specialized priority to the system's lightest users, who should be rewarded for their bandwidth conservation with the highest possible data rate access.
Therefore, there continues to be a need for improved data communications systems that can selectively apply more efficient rate-limiting schemes that offer a better overall user experience for the collective users of a shared data communications link.